Each year when Father's Day approaches, I'm reminded of the most important words my own father ever said to me. They didn't come in my toddlerhood, nor in adolescence. They came, rather, as I stood at the door of full adulthood, on the occasion of the sudden death of my paternal grandfather.

With Grandpa's passing, my father joined some 125 million other Americans who no longer had living fathers. Yet, even in that sorrowful moment, my father was able to offer me something that virtually all sons need from their fathers, but too few ever receive.

The year was 1984, I was 27 years old, between writing jobs, living a few blocks from the small Miami Beach apartment my grandfather had set up after his retirement. It was the first time in my life that Grandpa was close-by, and along with meals of pot roast and potatoes, I soaked up the stories of his harrowing childhood in Eastern Europe , desperate emigration, and eclectic life that spanned the century.

Then one day I got a phone call from a doctor. "I'm sorry to tell you this," came the voice, "but your grandfather has had a heart attack, and he has expired."

The next day, my father flew to south Florida from his home in Michigan . I picked him up at the airport, and we drove in silence to the hospital to identify Grandpa's body, collect his watch and wallet, and make arrangements to ship his body north for burial at my grandmother's side.

Then my father turned the key to my grandfather's home, and we began sorting the material remnants of the old man's life. We discovered curled black-and-white photos from the early years, key-chains from more recent times, passbooks, matchbooks, coins, coupons, and a pack of stale generic cigarettes. Working in different rooms, we'd occasionally exclaim to each other about a special find. Mostly we sorted in silence.

We kept at it until the glow of the afternoon sun had waned. Then my father and I collapsed in my grandfather's heavily pillowed living-room chairs, glasses of the old man's scotch in hand. We shared memories for awhile, then quiet. Finally, as the room faded into near-total darkness, I heard a guttural groan. At first, I was startled. Then I realized what was happening.

I had never before heard my father cry.

I rose, and knelt by his side. After a couple of minutes, he spoke. "I am crying not only for my father, but for me," he said. "His death means I'll never hear the words I've always wanted to hear from him: that he was proud of me, proud of the family I'd raised and the life I've lived."

And then my father directed his voice toward me, and he uttered those words that continue to resound, 17 years later. "So that you never have to feel this way too," he told me, "I want to tell you now how proud I am of you, of the choices you've made, of the life you've created."

Father-son relationships are almost always a struggle. In a survey I commissioned for my book, FatherLoss, 55 percent of sons reported having regrets about their relationships with their dads. One in five remained angry with their fathers, sometimes years or even decades after the older man's death.

My father and I had our differences. And yet, I noticed them begin to dissolve in the calm resonance of the blessing he offered me in my grandfather's apartment. In the months that followed, I felt stronger, more confident, especially as I re-started my career. It was as if my father represented not only himself but the larger world, and I had been accepted into it.

While researching FatherLoss, I met other men for whom a father's affirmation had made a powerful impact.

One recalled that when he was a rebellious teenager, his father beat him for failing in school. Twenty years later, the father visited his son for the first time since his son left home, and walked gape-mouthed through the million-dollar homes appointed with oak staircases and cabinets crafted by the younger man. The son recalled little more than the awestruck look on his father's face, and a subtle apology: I've underestimated you.

And that was enough for the son. It seems, in fact, that sons will forgive their fathers for almost anything if they can hear  in whatever way, at whatever age  the genuine affirmation of that most important man.

Similar words from our mothers don't seem to have the same effect. Mothers, who bring us into life as extensions of themselves, tend to love us no matter what. Not so our fathers. Whether for biological, cultural, or other reasons, a father's love often must be earned.

So this Father's Day, as we fathers accept presents and phone calls from our sons, let us remember the gift that so many of them desire from us, but will not request. Simple words, expressed sincerely: Son, I'm proud of you.

This article may be reprinted if the following paragraph is included at the end of the article:

Neil Chethik is a writer and speaker. He is author of FatherLoss: How sons deal with the deaths of their dads (Hyperion) and VoiceMale: What Husbands Really Think of Their Wives (Simon & Schuster). Reach him at neil@neilchethik.com or at www.NeilChethik.com .